Gematria (Heb. גימטריה, ultimately from the Greek γεωμετρια) is a numerological translation of a word or a group of words.  Historically, Hebrew and Greek have been the most common medium for the application of Gematria. The two main forms of Gematria are the "revealed" form and the "mystical form".

The word "Gematria" itself comes from the Greek word 'geometry'. Although Hebrew Gematria is the best known now, Greek Gematria predates it by many centuries. There is also a Gematria of Latin-script languages, dating from the early Middle Ages, and very possibly back into Roman times, too.

The most common form of gematria is used occasionally in the Talmud and Midrash and elaborately by many post-Talmudic commentators. It involves reading words and sentences as numbers, assigning numerical instead of phonetic value to each letter of the Hebrew alphabet. When read as numbers, they can be compared and contrasted with other words.  In a way, you could think of Gematria as a form of "checksum" that can be used to compare strings of text. 

Below, is a little program I wrote that will convert and compare two pieces of text using Gematria.  Feel free to enter any words you'd like. This code only works for the English alphabet - all numbers and non-English characters will be ignored.

This program uses the following Gematria code for assigning numeric values: